As far as gaming is concerned, AMD is always one step ahead. though Intel did release quad core first.
Personally I'll never go near Intel, they are a bunch of money grabbers, always making new chips with different slots, so you have to buy new motherboards etc, then their was the custom ram stuff they endorsed, again with different standards.. sure they made progress, but i think at the expense of people who want to buy the newest thing at the time rather than the best.
/ramble over